[PATCH v2 1/1] drm/amdgpu: Enable scatter gather display support

[Christian König]

Am 28.03.2018 um 00:22 schrieb Samuel Li:
> It's auto by default. For CZ/ST, auto setting enables sg display
> when vram size is small; otherwise still uses vram.
> This patch fixed some potential hang issue introduced by change
> "allow framebuffer in GART memory as well" due to CZ/ST hardware
> limitation.

Well that is still a NAK.

As discussed now multiple times please implement the necessary changes 
in Mesa.

Regards,
Christian.

>
> v2: Change default setting to auto, also some misc changes.
> Signed-off-by: Samuel Li <Samuel.Li at amd.com>
> ---
>   drivers/gpu/drm/amd/amdgpu/amdgpu.h               |  1 +
>   drivers/gpu/drm/amd/amdgpu/amdgpu_display.c       | 10 ++++++++--
>   drivers/gpu/drm/amd/amdgpu/amdgpu_display.h       |  2 ++
>   drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c           |  4 ++++
>   drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c            |  2 ++
>   drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c |  3 ++-
>   6 files changed, 19 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> index a7e2229..c942362 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> @@ -129,6 +129,7 @@ extern int amdgpu_lbpw;
>   extern int amdgpu_compute_multipipe;
>   extern int amdgpu_gpu_recovery;
>   extern int amdgpu_emu_mode;
> +extern int amdgpu_sg_display;
>   
>   #ifdef CONFIG_DRM_AMDGPU_SI
>   extern int amdgpu_si_support;
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
> index 5495b29..1e7b950 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.c
> @@ -513,8 +513,14 @@ uint32_t amdgpu_display_framebuffer_domains(struct amdgpu_device *adev)
>   #if defined(CONFIG_DRM_AMD_DC)
>   	if (adev->asic_type >= CHIP_CARRIZO && adev->asic_type < CHIP_RAVEN &&
>   	    adev->flags & AMD_IS_APU &&
> -	    amdgpu_device_asic_has_dc_support(adev->asic_type))
> -		domain |= AMDGPU_GEM_DOMAIN_GTT;
> +	    amdgpu_device_asic_has_dc_support(adev->asic_type)) {
> +		if (amdgpu_sg_display == 1)
> +			domain = AMDGPU_GEM_DOMAIN_GTT;
> +		else if (amdgpu_sg_display == -1) {
> +			if (adev->gmc.real_vram_size < AMDGPU_SG_THRESHOLD)
> +				domain = AMDGPU_GEM_DOMAIN_GTT;
> +		}
> +	}
>   #endif
>   
>   	return domain;
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.h
> index 2b11d80..2b25393 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_display.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_display.h
> @@ -23,6 +23,8 @@
>   #ifndef __AMDGPU_DISPLAY_H__
>   #define __AMDGPU_DISPLAY_H__
>   
> +#define AMDGPU_SG_THRESHOLD  (256*1024*1024)
> +
>   uint32_t amdgpu_display_framebuffer_domains(struct amdgpu_device *adev);
>   struct drm_framebuffer *
>   amdgpu_display_user_framebuffer_create(struct drm_device *dev,
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> index 1bfce79..19f11a5 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> @@ -132,6 +132,7 @@ int amdgpu_lbpw = -1;
>   int amdgpu_compute_multipipe = -1;
>   int amdgpu_gpu_recovery = -1; /* auto */
>   int amdgpu_emu_mode = 0;
> +int amdgpu_sg_display = -1;
>   
>   MODULE_PARM_DESC(vramlimit, "Restrict VRAM for testing, in megabytes");
>   module_param_named(vramlimit, amdgpu_vram_limit, int, 0600);
> @@ -290,6 +291,9 @@ module_param_named(gpu_recovery, amdgpu_gpu_recovery, int, 0444);
>   MODULE_PARM_DESC(emu_mode, "Emulation mode, (1 = enable, 0 = disable)");
>   module_param_named(emu_mode, amdgpu_emu_mode, int, 0444);
>   
> +MODULE_PARM_DESC(sg_display, "Enable scatter gather display, (1 = enable, 0 = disable, -1 = auto");
> +module_param_named(sg_display, amdgpu_sg_display, int, 0444);
> +
>   #ifdef CONFIG_DRM_AMDGPU_SI
>   
>   #if defined(CONFIG_DRM_RADEON) || defined(CONFIG_DRM_RADEON_MODULE)
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c
> index 1206301..f57c355 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_fb.c
> @@ -138,6 +138,8 @@ static int amdgpufb_create_pinned_object(struct amdgpu_fbdev *rfbdev,
>   	mode_cmd->pitches[0] = amdgpu_align_pitch(adev, mode_cmd->width, cpp,
>   						  fb_tiled);
>   	domain = amdgpu_display_framebuffer_domains(adev);
> +	if (domain & AMDGPU_GEM_DOMAIN_GTT)
> +		DRM_DEBUG_DRIVER("Scatter gather display: enabled\n");
>   
>   	height = ALIGN(mode_cmd->height, 8);
>   	size = mode_cmd->pitches[0] * height;
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index 68ab325..7e9f247 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -3074,7 +3074,8 @@ static int dm_plane_helper_prepare_fb(struct drm_plane *plane,
>   		domain = AMDGPU_GEM_DOMAIN_VRAM;
>   
>   	r = amdgpu_bo_pin(rbo, domain, &afb->address);
> -
> +	rbo->preferred_domains = domain;
> +	rbo->allowed_domains = domain;
>   	amdgpu_bo_unreserve(rbo);
>   
>   	if (unlikely(r != 0)) {